Hip replacement deaths decrease
27th September 2013 -- Death rates in the first 90 days following hip replacement surgery have halved since 2003, according to a study led by the University of Bristol on behalf of the National Joint Registry for England, Wales and Northern Ireland.
The research was led by Professor Ashley Blom from the University of Bristol and has been published in The Lancet. It found that between 2003 and 2011 mortality rates in the first 90 days following surgery halved from 0.6% to 0.3%.
Arthritis Research UK welcomed the findings as "great news for people in the UK who have osteoarthritis and require hip replacement surgery".
Four simple measures
A team of researchers from Bristol, Oxford, East Anglia and Exeter studied 409,096 patients who had hip replacements for osteoarthritis between 2003 and 2011. They found that the type of implant used did not affect mortality but four simple treatment options are associated with lower death rates. They are:
- The use of spinal anaesthetic. The likely explanation is that spinal anaesthetic reduces the need for general anaesthetic and immediate postoperative analgesia using morphine-like drugs that depress respiratory function. So the risk of postoperative pulmonary complications is reduced.
- The posterior surgical approach. The researchers believe the most likely reason is that the posterior approach results in more muscle preservation and therefore less bleeding and better mobilisation than the commonest alternative, the lateral approach.
- The use of chemical thromboprophylaxis with heparin (a measure using drugs to improve blood circulation).
- The use of mechanical thromboprophylaxis (items like compression stockings).
The researchers found that chemical and mechanical thromboprophylaxis act independently and both reduce mortality. They, therefore, believe the use of both, based on individual patient need, seems sensible.
Professor Blom says in a press release: "It is extremely good news that the risk of death after hip replacements has reduced so dramatically in England and Wales. It is also very exciting that we can further reduce the risk of post-operative death by adopting four relatively simple measures."
In an emailed statement, Jane Tadman from from the charity, Arthritis Research UK says: "Although not everyone who has arthritis will need hip replacement surgery, for many people, it’s their only hope to reduce the pain, disability and stiffness associated with the disease, giving people freedom from their pain, along with improved mobility.
"There are however always risks associated in having major surgery such as hip replacement surgery, so we advise people to discuss these risks with their surgeon before they decide to have a hip replacement."
The researchers also found that patients with certain medical conditions are at a much higher risk of death in the 90 days following surgery. Severe liver disease is associated with a ten-fold increase, a previous heart attack is associated with a three-fold increase and both diabetes and renal disease are associated with a two-fold increase.
However, overweight patients with a body mass index between 25 and 30 kg/m2 have a lower risk of death than those with a "normal" body mass index of 20-25 kg/m2. The researchers however say this result although intriguing, should be considered with some caution because of incomplete data on body-mass index.
Professor Blom says: "The finding that overweight people have a lower risk of death is surprising, but has been confirmed by other recent studies, and challenges some of our preconceptions. We need to concentrate efforts on reducing the risk of death in high risk groups such as those with severe liver disease."